Apparatus for the continuous heat treatment of metals or alloys



13% 4%, 1932" w. s. SMlTH ET AL APPARATUs FOR THE CONTINUOUS HEAT THEATMENT OF METALS OR ALLOYS Filed Dec. 22, 1931 Patented Get. 4, 1932 STATES PATENT OFFICE WILLOUGHBY; STATHAM SMITH, OF NEWTON POPPLEFORZDyALND CUTHBERT VICTOR HENRY GABNETT, OF SEVENOAKS, ENGLAND I APPARATUS FOR THE CONTINUOUS HEAT TREATMENT OF METALS OR ALLOYS Application filed December 22, 1931, Serial No. 582,612, and inGreat Britain December 24, 1930.

This invention relates to improvements in apparatus for the Continuous heat treatment of signalling conductors and more particu larly to a continuously loaded submarine signalling conductor which is subjected to heat treatment for the purpose of developing the magnetic properties of the layer or layers of loading material.

In the known method of 'heat'treating a Krarup conductor by the continuous process, the conductor is-wound from a supply drum through a tubular furnace to a take-up drum. For greater ease of control the furnace is preferably of the electric resistancetype, but other forms of heating such as oil or gas may also be used. On entering the furnace, the conductor first passes through a hot region where it is heated to the necessary temperature and it then passes through a cooling tube. Preferably the air in the tube of the furnace is displaced by an inert gas.

This method of heat-treatment is attended with several disadvantages, among which may be mentioned (l) mechanical damage to the conductor undergoing treatment as a result of direct contact with the tube of the furnace;

(2') accumulation in the tube of the furnace of sooty substances formed by the decomposition in the hot region of oil, grease or other carbonaceous materials introduced into the furnace by the loaded conductor. Such sooty materials may not only. choke the furnace tube, but may also react at the high temperature of the furnace with e. g. the magnetic material: upon the conductor, whereby the magnetic properties of the latter suffer deterioration;

of movement as that of the conductor.

The conveyor member or tape may be wound off and on to drums positioned at each 7 end of the furnace," the tape moving'into contact with the underside of the conductor just 'priorto its entering the mouth of the furnace.

Preferably a flat tape is employed which the furnace, the latter is separated from the conductor when it is preferably passed through a device for flattening the tape to facilitate its winding on the take up drum.

The invention is illustrated diagrammatically in the accompanying drawing in which Figure 1 is a view of a furnace showing the winding drums for a single conveyor,

Figures 2 and 3 are detail views on a larger scale,

Figures 4 and 5 aredetail views of an arrangement in which three conveyors'are employed.

In the drawing A indicates the furnace generally and B is the heating tube through which the conductor C is passed from supply to take up drums which are not shown. D is a water jacket. E are heating resistances.

According to the invention the conductor C in its passage through the furnace tube B is carried by a metal tape 1 which may be of copper or other suitable metal capable of resisting the temperature to which the furnace is heated in order to anneal the conductor.

The tape 1 is wound from a supply drum 2 through the furnace tube B to the take up drum 3 thus forming a support, upon which the conductor rests as it passes through the furnace.

The conveyor tape 1 is passed between a pair of shaping rollers 4 (see Figures 2 and 3) in order to give the tape a trough formation (in section) in order to locate the conductor.

On its separation from the conductor at thev exit end of the furnace the tape may be passed through flattening rolls 5 in order to facilitate the winding operation. These rolls, which may be grooved longitudinally, act to draw the tape from the furnace and are in driving connection as hereinafter explained with rolls 6 which act to draw the conductor from the furnace.

It is important that the linear speeds of the conductor and the conveyor tape should be identical in order that there may be no relative movement between them as they pass through the furnace. This is accomplished in the following manner :The conductor passes round the rolls 6 at a definite speed thence to the take up drum and, driven from the rolls 6 by means of a 1: 1 ratio coupling indicated at 6, are the rolls 5, by means of which the tape is drawn 0e. Itwilltherefore be seen that for any unit movement of the conductor, the tape must likewise move through unit distance.

In some cases two or more conveyor tapes may be used in association with the conductor for additional protection, or for any other reason, as it passes through the furnace.

An arrangement having three tapes is shown in Figures 4 and 5, the additional tapes being indicated at 7 and 8. The two. tapes 7 and 8 are each passed through a pair of shaping rollers 9' and 10 from which the curved tapes pass over guide rollers 11. Each guide roller has a guiding surface 12 shaped to accommodate the tape.

A heat treating furnace of the type above referred to (see for example, the specification of Patent No. 1,700,548) generally contains more than one furnace tube in order that several conductors may be treated simultaneously, in which case a conveyor tape or tapes is provided for each tube.

The invention is not limited to the narrow tubes of circular cross section (as illustrated in the drawing) such as are generally used for the heat treatment ofloadedv conductors, and the channel through the furnace may be of any desired shape and area of cross-section.

Another feature of the invention is that, before entering the furnace, the surface of the copper tape is oxidized e. heating in air.

At the high temperature of the furnace the copper oxide reacts with any substances of a chemically reducing nature produced by the decomposition of oil, grease or other carbonaceous matter associated with the conductor, oxidizing them to e. g. carbon dioxide and water, while it is'in itself reduced to metallic copper.

What we claim is a 1. In apparatus for the continuous heat treatment of signalling conductors the combination with a furnace, of a metal conveyor tape for supporting the conductor in its passage through the furnace, shaping means for shaping the tape to conform substantially to the shape of the conductor prior to its entering into engagement therewith, means for separating the tape from the conductor on exit from the furnace and means for drawing both the conductor and the tape through the furnace at the same rate. 7 p p 2. In apparatus for the continuous heat treatment of signalling conductors the combination with a furace, of a metalconveyor tape for supporting the conductor in its passage through the furnace, shaping rollers between which the conveyor tape is passed prior to lts enterin g into engagement with the con ,ductor, means for separating the tape from the conductor on eXit from the furnace, and means for drawing both the conductor and the tape rate.

'3. In apparatus for the continuous heat treatment of signalling conductors, the com bination with a furnace, of a metal conveyor tape for supporting the conductor in its pastape to conform substantiallyto the shape of the conductor prior to its entering into engagement therewith, rollers for drawing the conveyor tape from the furnace and being adapted to flatten the tape, means for drawing the conductor from the furnace, and a driving connection between said rollers and said means. I i 1 5. In apparatus for the continuous heat treatment of signalling conductors, the combination with a furnace of a plurality of metal conveyor tapes for the conductor in its passage through the furnace, shaping means for shaping the tapes to conform substantially to the shape of the conductor prior to the conductors entering into engagement with the tapes, and means for drawingboth the conductor and the tapes through the furnace at the same rate. Y

6. Apparatus as claimedin claim 1 coin prising a conveyor tape of copper.

7 In apparatus for the continuous heat treatment of signalling conductors the combination of a furnace through which the conductor is passed, a conveyer tape of metal which is of arcuate section to support the through the furnace at the same 

